coates



(No Model.)

B. G. GOATES.

AIR BRAKE.

No. 467,921. Patented Feb. 2, 1892.

WITNESSES: INVENTOR:

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ATTORNEYS NITED STATES PATENT OFFICE.

RAY G. CQATES, OF PUNTA ARENAS, COSTA RICA.

AIR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 467,921, dated February 2, 1892.

Application filed September 4, 1890. Serial No. 363,917. (No model.)

To aZZ whom, it may concern.-

Be it known that I, RAY G. COATES, of Punt-a Arenas, Costa Rica, Central America, have invented a new and useful Improvement in Air-Brakes, of which the following is a full, clear, and exact description.

The invention relates to air-brakes such as are shown and described in Letters Patent of the United States No. 138,827, granted to George \Vestinghouse, J r., on the 13th dayof May, 187 3, and in the application for Letters Patent, Serial No. 354E,728,.filed by me on the 9th day of June, 1890.

The object of the invention is to provide a new and improved air-brake in which the cutoff and exhaust of the brake-cylinder pressure is controlled by the action of the brakecylinder pressure and the train-pipe pressure on the one hand and the auxiliary-reservoir pressure on the other hand, each acting on a suitable flexible diaphragm.

The invention consists of a governing or a triple valve provided with an auxiliary diaphragm, subject to the pressure in the brakecylinder, to assist the pressure of the trainpipe acting upon the principal diaphragm of the ordinary valve in controlling the supply and discharge of the said cylinder for the purpose of maintaining in said cylinder any desirable pressure.

The invention also consists of certain parts and details and combinations of the same, as will be hereinafter more fully described, and then pointed out in the claim.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figure 1 is a sectional side elevation of the improvement in the position when the brakes are releasing or completely released, and Fig. 2 is a like view of the same in a difierent position. Fig. 3 is a detail section on line 3 3 of Fig. 2.

The improved governing or triple valve is provided with a casing A, in the upper part of which is arranged a diaghragin 13, forming on one side a compartment A and on its other side a compartment D, which latter is divided by a partition E from a third compartment F, in which is arranged an auXil iary diaphragm G, forming a compartment II in the lower part of the casiugA, the said compartment II being connected by an opening I in the lower cap of the said casing with outer air. The upper compartment A is connected with the train-pipe T P, the compartment D is connected with the auxiliary reservoir A R, and the third compartment F is connected with the brake-cylinder B C. The diaphragm 1 supports in its middle a valvestem N, which extends through a valve-seat E in the partition E into the compartment F, and on the said valve-stem is fitted to slide loosely avalv'e O,heldin thecompartmentDandadapted to be seated on the valve-seat. Ashoulder N on the valve-stem Nis adapted to lift the said valve 0 off the seatE. On the valve-stem l in the compartment F is formed a fork N In order that said fork K may obstruct the opening E as little as possible when the stem N is raised, as shown in Fig. 2, the upper side of the cross-bar of the fork is beveled each way from its longitudinal middle, thus forming, practically, a knife-edge. This construction is only essential, however, when the fork N is used as a stop to limit the upward movement of the stem 1T. The fork is connected. with the auxiliary diaphragm G, previously mentioned, in the middle of the latter being formed a valve-seat Q, adapted to be closed by a valve Q, serving to connect or disconnect the compartment F with or from the compartment H. A small vent is formed, as shown, between the compartment F and the hole forming the upper guide of the stem of valve Q in order to avoid any resistance to the mo tion of said valve that might be caused by the air above its said stem. This same result would, however, be attained if the valve-stem were fitted loosely in the hole in which it is guided. Between the train-pipe T P and the auxiliary reservoir A R a check-valve P is placed and so arranged as to allow pressure to pass from the train-pipe into the auxiliary reservoir, but not in the opposite direction. The train-pipe T P is charged by the engineer in the customary manner. The auxiliary reservoir A R is filled through the check-valve P andthe pressure passes to the compartment D. The diaphragm Bis subject to practically an equal pressure on each side and is consequently in equilibrium. The valve 0 is seated by the pressure of the air in compartment D. This is the normal condition of the valve and the one in which the brakes are released.

In operation, the release of pressure in the train-pipe T P causes the valve-stem N to rise by the action of the pressure in the compartment D against the under side of the diaphragm B, the pressure being supplied from the auxiliary reservoir A R. The first effect of this movement is to seat the valve Q on its seat Q, thereby closing the exhaust-opening I. A continued movement of the valvestem N opens the valve-seat E by the upward movement of the valve 0, caused by the shoulder N of the said Valve-stem striking against the under side of the valve 0. The seating of the valve Q before the valve 0 is raised is easily accomplished by the position of the shoulder N and also partially by the length of the projecting portion at the lower end of the valve Q. Pressure now passes into compartment F through the opening in the valveseat E (no, material obstructionbeing offered by the cross-bar of the fork N when beveled, as before described) and acts upon the brake cylinder and also upon the topside of the uxi ary diaph ag isvv force. or p essure on the auxiliary diaphragm G acts in the same direction as that in the train-pipe acts upon the main diaphragm B. hen the P e s r o h auxilia y iaph agm Geanels the lo s o pressure on the iap ra m B, then th valve-s em N w ll move 'dewn rnrd', thereby cutting ed the. further increase. of pre u e n e pa tme t F, and eense: que tly in h b ek y i er'B .C- f'the aphragm B an G are of equa w kin a eas, h se in the brakeylinder w ll equal the loss in the train-pipe Thevalve Q does not open in the same movement. which ses the V eSea owing togtheloss by the auxiliary diaphragm G of he smal are?) of t e uppe s l eee or thev'alve Q when the latter strikes against the lower cover of the melee A- If new th ein pipepressure in the compa tment A is ncreasedit e valvestem N will move still lowery and by the move.- men o he a x ary d aphragm G he valve Q is 9P- ed,th 1e eleas ng he'pressure in the co pa mentli of the'brake-ey i der-l T is release takes, place wi h the rise in the trainp pehe a a gement above described is the one preferredyet the construction may be varied considerably-for instance, the auxiliary diaphragm G may come against the lower valve-cover and the valve Q be fastened to the valve-stem N. It is,however, less delicately arranged and the exhaust does not take place simultaneously with the rise in the train-pipe. The valve Q may be in the side of the casing instead of the diaphragm. Proper connections would then be required. Any of the usual constructions of diaphragms may be used; also any of the customary valves that are suitable for this purpose may be employed, these being details easily changed by any one skilled in this particular art.

I am aware that it is no novelty to regulate the pressure in the brake-cylinder; also that triple valves for this purpose have been made in which the inlet and exhaust valves were loose on the main valve-stem, thereby effecting a result somewhat similar to my device.

In these former devices the control of the I pressure did not depend upon the utilization of the pressure existing or rising in the brakecylinder. I am also aware that'in triple valves the. use Of two diaphragms is no novelty.

Having thus fully described my invention, I claim as new and desire to secureb-y Letters Patent In an automatic air-brake, the combination, wi en au ia y a reser' e r, a train-p n and b ekercylinde of the connected casing A, havin g'an'apertnredpartition, a diaphragm B, and flilxiliary diaphragm G contained in Said CfiSing and subjectedIrespectivelygto the pressures i-infth ai -pipe. an brake-cylinder and diaphragm B, also to auxiliary-reservQ- pre sure, he valve comp ise .lef' t W pplem'entary valves or admission and dis- ,eher e or ai li e nd ew he bra ey inder, 311d 5! $9111, connected with theafo'resaid dianhre mis h eby the s pp y an discharge er pressu e in the b ake-cylinder are c ntrolled, substantially'as, and for the purpose pecified.

The foregoing specification of my new an improvedair-brake signed by me this eleventh (l th). d y f An u -E n th p ee e 0f the below-subscribed Witnesses.

RAY G. C-OATES. 

